The most recent economy trend in terms of power generation is directed towards renewable energy sources saving the environment and capable of insuring a certain extent of energy independence for consumers of power. One of the most significant such sources is the conversion of wind energy into electric energy that may be conveniently used by a lot of industrial and commercial facilities, as well as by households. The wind energy conversion is commonly provided by windmill farms including a number of windmill wheels (propellers) furnished with blades driven by a wind flow. However, such farms are expensive due to the size of windmill wheels determined by economical efficiency of the farms. They also occupy significant land areas that cannot be utilized for people residence. Some other factors also negatively influence the deployment of windmill farms: they are typically built on open land sites with frequent presence of strong winds, remote from most of consumers, which necessitates arrangement of electric power transmission therefrom causing additional losses of energy; they are dangerous to birds, etc.
Various devices alternative to the windmill farms have also been proposed. Exemplarily, U.S. Pat. No. 7,242,107, issued to Dempster, provides for “systems, methods and techniques by which a wind-powered energy generating platform, secured to an anchor, can pull (or winch) itself beneath the surface of the water and thereby avoid most of the significant effects of storms and waves. In more particularized aspects, a variable-buoyancy anchor is utilized, thereby facilitating the construction and transportation of the entire assembly.”
Devices of such kind still remain strongly weather-dependent, that is essentially may not generate enough power during low wind recessions. Other solutions have been proposed to accumulate energy during periods of strong winds, and use the accumulated energy during periods of low or no winds. One of the most popular methods is the conversion of excessive wind energy, rotating a turbine associated with an electric generator during the strong winds, into energy of compressed air, with a subsequent release of the compressed air to drive the generator during the low winds.
A typical example of the aforementioned method and a system therefor is described in U.S. Pat. No. 5,553,454 to Mortner that particularly teaches: “A system and method is provided for generating electrical energy by operatively connecting a generator to a drive shaft which is rotated axially when fan turbines connected to the drive shaft are rotated. The turbines are rotated by directing the release of air under pressure toward a plurality of blade surfaces of the turbines. The air under pressure is supplied from a plurality of storage tanks which are connected to one of a pair of pressure guide rings, which guide rings receive air under pressure from one or more connected tanks and direct the air through an output duct and toward the blade surfaces. The flow of air under pressure is controlled by a power regulator and controller which monitors the power output from the generator and transmits electrical signals to adjust the open and closed positioning of a tank output valve on each of the plurality of tanks. Alternatively, the drive shaft may be connected to a water pump, evaporating device, or the drive wheels of a motor vehicle for pollution-free powering of that device through the controlled release of compressed air in the plurality of tanks.”
The latter device is more efficient in terms of average yearly time of operation than the previously mentioned devices. However, the compressed air directed at the blade surfaces has parameters different from the wind flow parameters that complicates the design of such device. Besides, Mortner gives no indication on regulation of the rotational speed of turbines depending on the intenseness of wind flow, i.e. the regulation of rotational speed of the turbines during periods of high winds remains uncertain. The Mortner's system is not associated with any kind of electrical grid or reserve energy source, and thus would stop generating power when the pressure of compressed air in the storage tanks decreases below a certain level.